[Author: iwade]

Added GTMStringEncoding which is a generic base 2-128 encoder/decoder with support for custom character maps.

R=thomasvl
APPROVED=thomasvl
DELTA=723  (723 added, 0 deleted, 0 changed)

1 files changed, 309 insertions, 0 deletions

diff --git a/Foundation/GTMStringEncodingTest.m b/Foundation/GTMStringEncodingTest.m
new file mode 100644
index 0000000..82b7492
--- /dev/null
+++ b/Foundation/GTMStringEncodingTest.m
@@ -0,0 +1,309 @@
+//
+//  GTMStringEncodingTest.m
+//
+//  Copyright 2010 Google Inc.
+//
+//  Licensed under the Apache License, Version 2.0 (the "License"); you may not
+//  use this file except in compliance with the License.  You may obtain a copy
+//  of the License at
+//
+//  http://www.apache.org/licenses/LICENSE-2.0
+//
+//  Unless required by applicable law or agreed to in writing, software
+//  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+//  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+//  License for the specific language governing permissions and limitations under
+//  the License.
+//
+
+#import "GTMSenTestCase.h"
+#import "GTMStringEncoding.h"
+#import "GTMUnitTestDevLog.h"
+
+@interface GTMStringEncodingTest : GTMTestCase
+@end
+
+@implementation GTMStringEncodingTest
+
+// Empty inputs should result in empty outputs.
+- (void)testEmptyInputs {
+  GTMStringEncoding *coder = [GTMStringEncoding stringEncodingWithString:@"01"];
+
+  [GTMUnitTestDevLogDebug expectString:@"Empty input"];
+  STAssertEqualStrings([coder encode:[NSData data]], @"", nil);
+  [GTMUnitTestDevLogDebug expectString:@"Empty input"];
+  STAssertEqualObjects([coder encodeString:@""], @"", nil);
+  STAssertEqualObjects([coder decode:@""], [NSData data], nil);
+  STAssertEqualStrings([coder stringByDecoding:@""], @"", nil);
+}
+
+// Invalid inputs should result in nil outputs.
+- (void)testInvalidInputs {
+  GTMStringEncoding *coder = [GTMStringEncoding stringEncodingWithString:@"01"];
+
+  [GTMUnitTestDevLogDebug expectString:@"unable to convert buffer to ASCII"];
+  STAssertNil([coder decode:nil], nil);
+  [GTMUnitTestDevLogDebug expectString:@"Unexpected data in input pos 0"];
+  STAssertNil([coder decode:@"banana"], nil);
+}
+
+// Ignored inputs should be silently ignored.
+- (void)testIgnoreChars {
+  GTMStringEncoding *coder = [GTMStringEncoding stringEncodingWithString:@"01"];
+  [coder ignoreCharacters:@" \n-"];
+
+  char aa = 0xaa;
+  NSData *aaData = [NSData dataWithBytes:&aa length:sizeof(aa)];
+  STAssertEqualObjects([coder decode:@"10101010"], aaData, nil);
+
+  // Inputs with ignored characters
+  STAssertEqualObjects([coder decode:@"1010 1010"], aaData, nil);
+  STAssertEqualObjects([coder decode:@"1010-1010"], aaData, nil);
+  STAssertEqualObjects([coder decode:@"1010\n1010"], aaData, nil);
+
+  // Invalid inputs
+  [GTMUnitTestDevLogDebug expectString:@"Unexpected data in input pos 4"];
+  STAssertNil([coder decode:@"1010+1010"], nil);
+}
+
+#define ASSERT_ENCODE_DECODE_STRING(coder, decoded, encoded) do { \
+  STAssertEqualStrings([coder encodeString:decoded], encoded, nil); \
+  STAssertEqualStrings([coder stringByDecoding:encoded], decoded, nil); \
+} while (0)
+
+- (void)testBinary {
+  GTMStringEncoding *coder = [GTMStringEncoding binaryStringEncoding];
+
+  [GTMUnitTestDevLogDebug expectString:@"Empty input"];
+  ASSERT_ENCODE_DECODE_STRING(coder, @"", @"");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"f", @"01100110");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"fo", @"0110011001101111");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foo", @"011001100110111101101111");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foob", @"011001100110111101101111"
+                                               "01100010");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"fooba", @"011001100110111101101111"
+                                                "0110001001100001");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foobar", @"011001100110111101101111"
+                                                 "011000100110000101110010");
+
+  // All values, generated with:
+  // perl -le 'print unpack "B*", join("", map chr, 0..255)'
+  NSString *allValues = @""
+  "0000000000000001000000100000001100000100000001010000011000000111000010000000"
+  "1001000010100000101100001100000011010000111000001111000100000001000100010010"
+  "0001001100010100000101010001011000010111000110000001100100011010000110110001"
+  "1100000111010001111000011111001000000010000100100010001000110010010000100101"
+  "0010011000100111001010000010100100101010001010110010110000101101001011100010"
+  "1111001100000011000100110010001100110011010000110101001101100011011100111000"
+  "0011100100111010001110110011110000111101001111100011111101000000010000010100"
+  "0010010000110100010001000101010001100100011101001000010010010100101001001011"
+  "0100110001001101010011100100111101010000010100010101001001010011010101000101"
+  "0101010101100101011101011000010110010101101001011011010111000101110101011110"
+  "0101111101100000011000010110001001100011011001000110010101100110011001110110"
+  "1000011010010110101001101011011011000110110101101110011011110111000001110001"
+  "0111001001110011011101000111010101110110011101110111100001111001011110100111"
+  "1011011111000111110101111110011111111000000010000001100000101000001110000100"
+  "1000010110000110100001111000100010001001100010101000101110001100100011011000"
+  "1110100011111001000010010001100100101001001110010100100101011001011010010111"
+  "1001100010011001100110101001101110011100100111011001111010011111101000001010"
+  "0001101000101010001110100100101001011010011010100111101010001010100110101010"
+  "1010101110101100101011011010111010101111101100001011000110110010101100111011"
+  "0100101101011011011010110111101110001011100110111010101110111011110010111101"
+  "1011111010111111110000001100000111000010110000111100010011000101110001101100"
+  "0111110010001100100111001010110010111100110011001101110011101100111111010000"
+  "1101000111010010110100111101010011010101110101101101011111011000110110011101"
+  "1010110110111101110011011101110111101101111111100000111000011110001011100011"
+  "1110010011100101111001101110011111101000111010011110101011101011111011001110"
+  "1101111011101110111111110000111100011111001011110011111101001111010111110110"
+  "111101111111100011111001111110101111101111111100111111011111111011111111";
+  char allValuesBytes[256];
+  for (NSUInteger i = 0; i < sizeof(allValuesBytes); i++)
+    allValuesBytes[i] = i;
+  NSData *allValuesData = [NSData dataWithBytes:&allValuesBytes
+                                         length:sizeof(allValuesBytes)];
+
+  STAssertEqualObjects([coder decode:allValues], allValuesData, nil);
+  STAssertEqualStrings([coder encode:allValuesData], allValues, nil);
+}
+
+- (void)testBase64 {
+  // RFC4648 test vectors
+  GTMStringEncoding *coder = [GTMStringEncoding rfc4648Base64StringEncoding];
+
+  [GTMUnitTestDevLogDebug expectString:@"Empty input"];
+  ASSERT_ENCODE_DECODE_STRING(coder, @"", @"");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"f", @"Zg==");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"fo", @"Zm8=");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foo", @"Zm9v");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foob", @"Zm9vYg==");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"fooba", @"Zm9vYmE=");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foobar", @"Zm9vYmFy");
+
+  // All values, generated with:
+  // python -c 'import base64; print base64.b64encode("".join([chr(x) for x in range(0, 256)]))'
+  NSString *allValues = @""
+  "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8gISIjJCUmJygpKissLS4vMDEyMzQ1Njc4"
+  "OTo7PD0+P0BBQkNERUZHSElKS0xNTk9QUVJTVFVWV1hZWltcXV5fYGFiY2RlZmdoaWprbG1ub3Bx"
+  "cnN0dXZ3eHl6e3x9fn+AgYKDhIWGh4iJiouMjY6PkJGSk5SVlpeYmZqbnJ2en6ChoqOkpaanqKmq"
+  "q6ytrq+wsbKztLW2t7i5uru8vb6/wMHCw8TFxsfIycrLzM3Oz9DR0tPU1dbX2Nna29zd3t/g4eLj"
+  "5OXm5+jp6uvs7e7v8PHy8/T19vf4+fr7/P3+/w==";
+  char allValuesBytes[256];
+  for (NSUInteger i = 0; i < sizeof(allValuesBytes); i++)
+    allValuesBytes[i] = i;
+  NSData *allValuesData = [NSData dataWithBytes:&allValuesBytes
+                                         length:sizeof(allValuesBytes)];
+
+  STAssertEqualObjects([coder decode:allValues], allValuesData, nil);
+  STAssertEqualStrings([coder encode:allValuesData], allValues, nil);
+}
+
+- (void)testBase64Websafe {
+  // RFC4648 test vectors
+  GTMStringEncoding *coder =
+      [GTMStringEncoding rfc4648Base64WebsafeStringEncoding];
+
+  [GTMUnitTestDevLogDebug expectString:@"Empty input"];
+  ASSERT_ENCODE_DECODE_STRING(coder, @"", @"");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"f", @"Zg==");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"fo", @"Zm8=");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foo", @"Zm9v");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foob", @"Zm9vYg==");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"fooba", @"Zm9vYmE=");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foobar", @"Zm9vYmFy");
+
+  // All values, generated with:
+  // python -c 'import base64; print base64.urlsafe_b64encode("".join([chr(x) for x in range(0, 256)]))'
+  NSString *allValues = @""
+  "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8gISIjJCUmJygpKissLS4vMDEyMzQ1Njc4"
+  "OTo7PD0-P0BBQkNERUZHSElKS0xNTk9QUVJTVFVWV1hZWltcXV5fYGFiY2RlZmdoaWprbG1ub3Bx"
+  "cnN0dXZ3eHl6e3x9fn-AgYKDhIWGh4iJiouMjY6PkJGSk5SVlpeYmZqbnJ2en6ChoqOkpaanqKmq"
+  "q6ytrq-wsbKztLW2t7i5uru8vb6_wMHCw8TFxsfIycrLzM3Oz9DR0tPU1dbX2Nna29zd3t_g4eLj"
+  "5OXm5-jp6uvs7e7v8PHy8_T19vf4-fr7_P3-_w==";
+  char allValuesBytes[256];
+  for (NSUInteger i = 0; i < sizeof(allValuesBytes); i++)
+    allValuesBytes[i] = i;
+  NSData *allValuesData = [NSData dataWithBytes:&allValuesBytes
+                                         length:sizeof(allValuesBytes)];
+
+  STAssertEqualObjects([coder decode:allValues], allValuesData, nil);
+  STAssertEqualStrings([coder encode:allValuesData], allValues, nil);
+}
+
+- (void)testBase32 {
+  // RFC4648 test vectors
+  GTMStringEncoding *coder = [GTMStringEncoding rfc4648Base32StringEncoding];
+
+  [GTMUnitTestDevLogDebug expectString:@"Empty input"];
+  ASSERT_ENCODE_DECODE_STRING(coder, @"", @"");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"f", @"MY======");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"fo", @"MZXQ====");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foo", @"MZXW6===");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foob", @"MZXW6YQ=");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"fooba", @"MZXW6YTB");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foobar", @"MZXW6YTBOI======");
+
+  // All values, generated with:
+  // python -c 'import base64; print base64.b32encode("".join([chr(x) for x in range(0, 256)]))'
+  NSString *allValues = @""
+  "AAAQEAYEAUDAOCAJBIFQYDIOB4IBCEQTCQKRMFYYDENBWHA5DYPSAIJCEMSCKJRHFAUSUKZMFUXC"
+  "6MBRGIZTINJWG44DSOR3HQ6T4P2AIFBEGRCFIZDUQSKKJNGE2TSPKBIVEU2UKVLFOWCZLJNVYXK6"
+  "L5QGCYTDMRSWMZ3INFVGW3DNNZXXA4LSON2HK5TXPB4XU634PV7H7AEBQKBYJBMGQ6EITCULRSGY"
+  "5D4QSGJJHFEVS2LZRGM2TOOJ3HU7UCQ2FI5EUWTKPKFJVKV2ZLNOV6YLDMVTWS23NN5YXG5LXPF5"
+  "X274BQOCYPCMLRWHZDE4VS6MZXHM7UGR2LJ5JVOW27MNTWW33TO55X7A4HROHZHF43T6R2PK5PWO"
+  "33XP6DY7F47U6X3PP6HZ7L57Z7P674======";
+  char allValuesBytes[256];
+  for (NSUInteger i = 0; i < sizeof(allValuesBytes); i++)
+    allValuesBytes[i] = i;
+  NSData *allValuesData = [NSData dataWithBytes:&allValuesBytes
+                                         length:sizeof(allValuesBytes)];
+
+  STAssertEqualObjects([coder decode:allValues], allValuesData, nil);
+  STAssertEqualStrings([coder encode:allValuesData], allValues, nil);
+}
+
+- (void)testBase32Hex {
+  // RFC4648 test vectors
+  GTMStringEncoding *coder = [GTMStringEncoding rfc4648Base32HexStringEncoding];
+
+  [GTMUnitTestDevLogDebug expectString:@"Empty input"];
+  ASSERT_ENCODE_DECODE_STRING(coder, @"", @"");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"f", @"CO======");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"fo", @"CPNG====");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foo", @"CPNMU===");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foob", @"CPNMUOG=");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"fooba", @"CPNMUOJ1");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foobar", @"CPNMUOJ1E8======");
+
+  // All values, generated with:
+  // python -c 'import base64; print base64.b32encode("".join([chr(x) for x in range(0, 256)]))' | tr A-Z2-7 0-9A-V
+  NSString *allValues = @""
+  "000G40O40K30E209185GO38E1S8124GJ2GAHC5OO34D1M70T3OFI08924CI2A9H750KIKAPC5KN2"
+  "UC1H68PJ8D9M6SS3IEHR7GUJSFQ085146H258P3KGIAA9D64QJIFA18L4KQKALB5EM2PB9DLONAU"
+  "BTG62OJ3CHIMCPR8D5L6MR3DDPNN0SBIEDQ7ATJNF1SNKURSFLV7V041GA1O91C6GU48J2KBHI6O"
+  "T3SGI699754LIQBPH6CQJEE9R7KVK2GQ58T4KMJAFA59LALQPBDELUOB3CLJMIQRDDTON6TBNF5T"
+  "NQVS1GE2OF2CBHM7P34SLIUCPN7CVK6HQB9T9LEMQVCDJMMRRJETTNV0S7HE7P75SRJUHQFATFME"
+  "RRNFU3OV5SVKUNRFFU7PVBTVPVFUVS======";
+  char allValuesBytes[256];
+  for (NSUInteger i = 0; i < sizeof(allValuesBytes); i++)
+    allValuesBytes[i] = i;
+  NSData *allValuesData = [NSData dataWithBytes:&allValuesBytes
+                                         length:sizeof(allValuesBytes)];
+
+  STAssertEqualObjects([coder decode:allValues], allValuesData, nil);
+  STAssertEqualStrings([coder encode:allValuesData], allValues, nil);
+}
+
+- (void)testHex {
+  // RFC4648 test vectors
+  GTMStringEncoding *coder = [GTMStringEncoding hexStringEncoding];
+
+  [GTMUnitTestDevLogDebug expectString:@"Empty input"];
+  ASSERT_ENCODE_DECODE_STRING(coder, @"", @"");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"f", @"66");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"fo", @"666F");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foo", @"666F6F");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foob", @"666F6F62");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"fooba", @"666F6F6261");
+  ASSERT_ENCODE_DECODE_STRING(coder, @"foobar", @"666F6F626172");
+
+  // All Values, generated with:
+  // python -c 'import binascii; print binascii.b2a_hex("".join([chr(x) for x in range(0, 256)])).upper()'
+  NSString *allValues = @""
+  "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F202122232425"
+  "262728292A2B2C2D2E2F303132333435363738393A3B3C3D3E3F404142434445464748494A4B"
+  "4C4D4E4F505152535455565758595A5B5C5D5E5F606162636465666768696A6B6C6D6E6F7071"
+  "72737475767778797A7B7C7D7E7F808182838485868788898A8B8C8D8E8F9091929394959697"
+  "98999A9B9C9D9E9FA0A1A2A3A4A5A6A7A8A9AAABACADAEAFB0B1B2B3B4B5B6B7B8B9BABBBCBD"
+  "BEBFC0C1C2C3C4C5C6C7C8C9CACBCCCDCECFD0D1D2D3D4D5D6D7D8D9DADBDCDDDEDFE0E1E2E3"
+  "E4E5E6E7E8E9EAEBECEDEEEFF0F1F2F3F4F5F6F7F8F9FAFBFCFDFEFF";
+  char allValuesBytes[256];
+  for (NSUInteger i = 0; i < sizeof(allValuesBytes); i++)
+    allValuesBytes[i] = i;
+  NSData *allValuesData = [NSData dataWithBytes:&allValuesBytes
+                                         length:sizeof(allValuesBytes)];
+
+  STAssertEqualObjects([coder decode:allValues], allValuesData, nil);
+  STAssertEqualStrings([coder encode:allValuesData], allValues, nil);
+
+  // Lower case
+  STAssertEqualObjects([coder decode:[allValues lowercaseString]],
+                       allValuesData, nil);
+
+  // Extra tests from GTMNSData+HexTest.m
+  NSString *testString = @"1C2F0032F40123456789ABCDEF";
+  char testBytes[] = { 0x1c, 0x2f, 0x00, 0x32, 0xf4, 0x01, 0x23,
+                       0x45, 0x67, 0x89, 0xab, 0xcd, 0xef };
+  NSData *testData = [NSData dataWithBytes:testBytes length:sizeof(testBytes)];
+  STAssertEqualStrings([coder encode:testData], testString, nil);
+  STAssertEqualObjects([coder decode:testString], testData, nil);
+
+  // Invalid inputs
+  [GTMUnitTestDevLogDebug expectString:@"Incomplete trailing data"];
+  STAssertNil([coder decode:@"1c2f003"], nil);
+  [GTMUnitTestDevLogDebug expectString:@"Unexpected data in input pos 7"];
+  STAssertNil([coder decode:@"1c2f00ft"], nil);
+  [GTMUnitTestDevLogDebug expectString:@"Unexpected data in input pos 4"];
+  STAssertNil([coder decode:@"abcd<C3><A9>f"], nil);
+}
+
+@end